Turns out that even though the Mexican, as he bills himself, is writing a book about Mexican restaurants across the United States, he's never before encountered a Mexican hamburger.

We're not talking a green chile cheeseburger, of course, or any other burger smothered with guac and other allegedly Mexican accessories. We're talking a Mexican hamburger that takes a grilled patty of ground beef -- that most American of food items -- and tucks it into a tortilla with some refried beans, then smothers the whole thing in green chile.

Is Colorado truly the only place where you find a Mexican hamburger? And where did it get its start? Legend points to Joe's Buffet, a long-gone dive at 753 Santa Fe that used to serve up hundreds of these plates a day.